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| -rw-r--r-- | coreutils/nproc.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/coreutils/nproc.c b/coreutils/nproc.c new file mode 100644 index 000000000..d7c6a4ba1 --- /dev/null +++ b/coreutils/nproc.c @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2017 Denys Vlasenko <vda.linux@googlemail.com> + * + * Licensed under GPLv2, see LICENSE in this source tree + */ +//config:config NPROC +//config: bool "nproc" +//config: default y +//config: help +//config: Print number of CPUs + +//applet:IF_NPROC(APPLET(nproc, BB_DIR_USR_BIN, BB_SUID_DROP)) + +//kbuild:lib-$(CONFIG_NPROC) += nproc.o + +//usage:#define nproc_trivial_usage +//usage: "" +//TODO: "[--all] [--ignore=N]" +//usage:#define nproc_full_usage "\n\n" +//usage: "Print number of CPUs" + +#include <sched.h> +#include "libbb.h" + +int nproc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int nproc_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM) +{ + unsigned long mask[1024]; + unsigned i, count = 0; + + //applet_long_options = ...; + //getopt32(argv, ""); + + //if --all, count /sys/devices/system/cpu/cpuN dirs, else: + + if (sched_getaffinity(0, sizeof(mask), (void*)mask) == 0) { + for (i = 0; i < ARRAY_SIZE(mask); i++) { + unsigned long m = mask[i]; + while (m) { + if (m & 1) + count++; + m >>= 1; + } + } + } + if (count == 0) + count++; + printf("%u\n", count); + + return 0; +} |